Suppliers of potable water would benefit from a sustainable business as long as consumers continue to prefer their brand. Some of the reasons for choosing a particular brand include water quality, cost of the finished...Suppliers of potable water would benefit from a sustainable business as long as consumers continue to prefer their brand. Some of the reasons for choosing a particular brand include water quality, cost of the finished product, reliability of supply, and supplier ethics. These important determinant factors form the basis of this work. The objective is to delineate consumer preferences for water supplied to the Njala campus community, in southern Sierra Leone, and the underlying determinant factors. A list of questions administered to 140 respondents, are used to help achieve the objective. The results of water quality tests are also used to determine if quality has anything to do with consumer preference. The Oxfam Delagua water testing kit is customized to incubate and enhance counting of fecal and no-fecal coliform bacteria in water samples. Bacterial contamination is the major concern in the study area. The survey results reveal the consumers prefer package water for drinking. Treated water from Tia River is only used for other domestic purposes. The consumers do not trust the quality of water supplied from Tia River, albeit filtration and disinfection at the University’s treatment center. This distrust is confirmed by the bacterial test. None of the campus water sources meet recommended guidelines for drinking water. The consumers are, however, willing to shift preference from package to tap drinking water if treatment comes with quality assurance. The university could benefit through economic gratification, customer protection, and reduced plastic waste from package drinking water.展开更多
The safety of water is usually determined by comparing its quality to recommended standards. The objective of this work was to determine whether the water supplied on Njala Campus is safe for drinking. The quality par...The safety of water is usually determined by comparing its quality to recommended standards. The objective of this work was to determine whether the water supplied on Njala Campus is safe for drinking. The quality parameters investigated include coliform bacteria, turbidity, conductivity, total dissolved solids and nitrates. Samples were stored in a cooler with ice and transported to the laboratory within 30 minutes of collection. A checklist of questions to know the perception of residents was administered. According to the physical and biological results, the water is not safe for consumption. The turbidity and microbial counts were too high in most samples both in the wet and dry seasons. Additionally, over 80% of the respondents did not trust the water supply system. Most of them treat the supplied water by either boiling or disinfection before use. Most respondents complained of water-borne diseases but were not clear whether it is related to the water supplied. The chemical parameters, however, were acceptable: nitrate levels were low. In conclusion, the water is not safe for consumption as far as the physical and biological parameters are concerned. The campus water supply system needs improvement in terms of conveying raw and finished water, filter optimization, and satisfying the chlorine demand.展开更多
This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in...This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup>) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p < 0.05) influenced grain yield production. Mean grain yields and economic parameter estimates increased with increasing nitrogen rates, with the 30 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup> plots exhibiting the lowest and highest grain yields of 1238 kg∙ha<sup>−</sup><sup>1</sup> and 2098 kg∙ha<sup>−</sup><sup>1</sup>, respectively. Variety and nitrogen effects on partial factor productivity (PFP<sub>N</sub>), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p < 0.05) by these factors. The highest PFP<sub>N</sub> (41.3 kg grain kg<sup>−</sup><sup>1</sup>∙N) and AEN (29.4 kg grain kg<sup>−</sup><sup>1</sup>∙N) were obtained in the 30 kg∙N∙ha<sup>−</sup><sup>1</sup> plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL<sup>−</sup><sup>1</sup> spent on N) were obtained in the 180 kg∙N∙ha<sup>−</sup><sup>1</sup>. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fertilization and improved farming practices that could be exploited for increased productivity of maize.展开更多
This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. T...This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Foya Wulleh, Njala experimental site in Sierra Leone during 2020 and 2021 cropping seasons in a randomized complete block design with three replications. A total of 30 genotypes comprising 26 breeding lines, two improved and two local genotypes were assessed. Results showed a significant (p < 0.05) linear relationship between leaf CNP and grasshopper infestation (incidence and severity of damage) among cassava genotypes. Findings showed that the higher leaf CNP, the lower the grasshopper infestation in cassava genotypes. About two genotypes (Cooksoon and Cocoa) had low leaf CNP;three genotypes (TR0020, TR0037 and TR0013) CNP had moderately low leaf CNP;eight genotypes (SLICASS 6, TR0029, TR0032, TR0011, TR0012, TR0016-1/17, TR0002 and TR0010) had intermediate leaf CNP;seven (TR0009, TR0015-1/17, TR0036, TR0022-1/17, SLICASS 4, TR0007 and TR0026-1/17) had moderately high leaf CNP;eight (TR0008, TR0019-1/17, TR0006, TR0005, TR0021, TR0021-1/17, TR0022 and TR0024-1/17) had high leaf CNP;and two genotypes (TR0001 and TR0018-1/17) had very high leaf CNP. This suggests the indirect dependence of leaf cyanogenic potential on grasshopper infestation (incidence and severity of damage) in cassava that could be exploited for the genetic improvement of cassava for improved resistance to grasshopper infestation, nutrition and utilization of the crop.展开更多
The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6)...The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6). Fresh cassava roots harvested from the Department of Agricultural Engineering were peeled, washed and grated before fermentation and starch extraction. Fermentation was carried out under separate aerobic and anaerobic conditions for a period of Seven days. Physicochemical analyses were conducted at the Postharvest Food and Bioprocess Engineering Laboratory of the Department of Agricultural and Bio-System Engineering, Njala University to determine the solubility, water absorption capacity and swelling power of starch extracts obtained from various experimental treatments. Fermentation method and duration had significant effects on the solubility, water absorption capacity (WAC) and swelling power (SP) of starch extracts. Maximum solubility and WAC were recorded on the fifth day, for both cassava varieties tested, with apparent significant difference resulting from the two gratering bands (i.e., with 1.5-inch nail hole and 4-inch nail hole sizes, respectively). While swelling power increased consistently with temperature for starch obtained from SLICASS-11 variety, an irregular pattern was observed for SLICASS-6 variety. A multiple correlation analysis proposes a significant and weak correlation between temperature, WAC (+0.150) and swelling power (+0.048). Also multiple correlation analyses suggest a significant correlation between fermentation period, the functional properties of starch extracts obtained from both fermentation methods and cassava varieties (i.e., solubility (−0.226), water absorption capacity (+0.301) and swelling power (+0.329)).展开更多
Low nutrient density and bulkiness of complementary foods, early introduction of solid foods, and unhygienic practices during weaning stage of a child predispose infants to malnutrition, growth retardation, infection ...Low nutrient density and bulkiness of complementary foods, early introduction of solid foods, and unhygienic practices during weaning stage of a child predispose infants to malnutrition, growth retardation, infection and high mortality. In most West African countries, especially in Sierra Leone, the use of a variety of home-made complementary foods prepared from locally grown foodstuffs during the weaning process is popular, with products traditionally known as pap (mesh rice water) fofo from cassava, ogi, gari, akamu and couscous. Sierra Leone is one of the countries in West Africa that has been reported to have a challenging situation with regards to complementary foods, and little effort has so far been done to improve the situation. Despite these challenges, very little work has been directed towards the development of complementary foods using local foodstuffs as practiced in some other African countries. This situation has serious impact on the lives of infants in Sierra Leone, thus increasing the rate of mortality in the country. Complementary food situation in Sierra Leone was reviewed in terms of the past and present practices as well as the types of complementary foods used in Sierra Leone. Thus, the objective of this review was to discuss the complementary food situation in Sierra Leone: Nutritional problems and possible strategies. Formulation of high nutritive value home-made complementary foods in the country was recommended using traditional food processing techniques such as fermentation and germination, since these methods are simple, and could easily be employed at household and community levels without the use of sophisticated machinery. Nonetheless, it was recently reported that a product from the orange-flesh sweet potato could address the issue of complementary food in the country as it is easy to prepare, and the products are easily available in the rural area and even urban settings. Other recommendations made include: community nutrition education, the development of weaning recipe book, reduction in the workload of the suckling mother, promotion of breastfeeding and increased maternity leave period, which were suggested to be the most immediate possible strategies for the problems highlighted.展开更多
Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and...Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and service. Unsafe food can cause illness keeping people from achieving their full potential and death. This was a descriptive study that uses a mixed method approach to derive insights into the characteristics of food vendors related to demography, knowledge, practices, infrastructure, compliance and recommendation for a policymaking framework. Using the Lemeshows’ sample size formula, 473 vendors from formal (restaurants) and informal (cookri-baffa/table top) sites were interviewed and observed. We found from discussions that respondents had a good understanding on how to keep food safe. However, observed practices were poor 93% handled food with their bare hands, 83% did not cover their hair, and 76% did not wear an apron whilst handling, preparing or serving food, 61% did not keep their finger nails clean or short and 57% did not wash their hand before preparing or serving food. Over half (51%) had access to a toilet but 32% reported their use required payment and emphasized their poor condition/inadequate management. Nearly half (47%) of the vending sites did not have a handwashing facility, with soap and water available. Only 7% reported having any authority oversight of food safety. Food safety and hygiene practices in most cookri shops and restaurants was ‘poor’ with very limited surveillance system in place by competent authorities for compliance of food operators. Hand washing, clean surroundings, and covered food were the most common and emphasized practices to mitigate the risks associated with unsafe food.展开更多
This study evaluated the variation in yellow root cassava (Manihot esculentus Crantz) genotypes and phenotypic relationship for selected postharvest and morphological traits. The trial was established at the Njala Agr...This study evaluated the variation in yellow root cassava (Manihot esculentus Crantz) genotypes and phenotypic relationship for selected postharvest and morphological traits. The trial was established at the Njala Agricultural Research Centre experimental site, Njala, during 2017/2018 cropping season in a randomized complete block design with three replications. Findings showed that the higher the total carotene content (TCC) in yellow flesh cassava genotypes, the longer the rate of postharvest physiological deterioration (PPD). Genotypes TR-0051-TCC/17 and TR-0012-TCC/17 recorded higher TCC (18.9 µg/g and 13.6 µg/g) and longer rate of PPD (4.29 and 3.14), respectively. Genotypes TR-0051-TCC/17, TR-0016-TCC/17, TR-0028-TCC/17, TR-0012-TCC/17 and TR-0020-TCC/17 had the highest TCC values of 18.9 µg/g, 16.09 µg/g, 14.72 µg/g, 13.6 µg/g and 11.23 µg/g with corresponding higher color chart values of 6, 6, 6, 5, and 6, respectively. This suggests the direct dependence of TCC on the root parenchyma color intensity in yellow flesh cassava genotypes. Findings also show a direct relationship between morphological and postharvest traits in yellow flesh cassava genotypes that could be exploited for the genetic improvement of cassava for increased shelf life, nutrition and related quality traits, as well as conservation and utilization of the crop.展开更多
Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for ha...Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.展开更多
Artificial fishponds play a pivotal role in global aquaculture, serving as a source of livelihood and nourishment for many communities. Ensuring the sustained health and productivity of Fishes in these environments re...Artificial fishponds play a pivotal role in global aquaculture, serving as a source of livelihood and nourishment for many communities. Ensuring the sustained health and productivity of Fishes in these environments relies heavily on water quality management. This assessment was done to determine the water quality of ten artificial fishponds in the south-eastern part of Sierra Leone using twelve physicochemical factors (pH, BOD, EC, TDS, turbidity, COD, Fe<sup>2+</sup>, Mg<sup>2+</sup>, Ca<sup>2+</sup>, NH<sub>3</sub>, , and alkalinity) to find out the Water Quality Index (WQI) and spatial distribution of respective parameters. The assessment of artificial fishponds using WQI and Inverse Distant Weighting (IDW) integration represents a relatively underexplored area within the domain of environmental water resources. The WQI was determined using the “Weighted Arithmetic Water Quality Index’’ method. The results of WQI in the study area range from 65.05 to 147.26. Several locations have water quality deemed unsuitable for consumption, while others range from good to very poor. It is essential to address and improve water quality in locations categorized as unsuitable for consumption and very poor to ensure safe and healthy water sources. It was also clear from the calculation that the smaller the mean concentration value of the pH as compared to the ideal value (7), the smaller the WQI value and the better the water quality. To keep the artificial fishpond water in good condition, mass domestic use should be controlled, and draining of surrounding organic matter should be stopped in ponds Bo_001, Kenema_001, and Kenema_002.展开更多
Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasi...Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasing across the globe. In this study, the physical parameters of potable well waters in the key mining areas in Nimikoro and Tankoro Chiefdoms in Kono District were analyzed for compliance with drinking water quality standard. To do this, both unpurged and purged well water samples were collected once every month for a period of one year. Some of the well water properties like temperature, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were measured on site and others determined in the laboratory. The data collected from the laboratory analyses were statistically analyzed in MS Excel, SPSS and ArcGIS environments for quality trends in time-space fabric. The results showed that well water quality in the study area generally fell short of drinking water quality standards of Sierra Leone and WHO. There were high temperature and turbidity during the dry season and then high TDS and EC during the rainy season. Temperature and turbidity also significantly influenced well water quality in the study area, much more than TDS and EC. The implications for drinking water of lower quality than the standard could be huge for the local population and therefore needs the attention of stakeholders in the study area and decision makers in the country.展开更多
This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) de...This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) determine calcium and magnesium, 3) determine available iron. The following hypotheses were put forward;H<sub>0</sub><sub>a</sub>: there is no significant difference in the concentration levels between Ca and Mg in the study area, H<sub>1</sub><sub>a</sub>: there is significant difference in the concentration levels between Ca and Mg in the study area, H<sub>0</sub><sub>b</sub>: there is no significant difference in the concentration levels between Na and K in the study area, H<sub>1</sub><sub>b</sub>: there is significant difference in the concentration levels between Na and K in the study area. Six locations were used to collect samples with the aid of scoop and gravel free auger (at varying depths of 0 - 5 cm and 5 - 10 cm) which are Wellington Industrial Estate Area 1 (WIEL 1), (WIEL 2), (WIEL 3), (WIEL 4), (WIEL 5), (WIEL 6);the samples were given laboratory treatment. Flame photometer, EDTA, and Spectrophotometer were used in the determinations of sodium and potassium, calcium and magnesium, and available iron respectively. The results indicated that levels of potassium were in medium range (moderately high);sodium levels were generally low when compared to Brook’s classification table. Levels of calcium were generally low and those of magnesium were moderate based on Brook’s table of classification. Levels of available iron which fall within the range of Quijano-Guerta (2003) were high;this implies such levels can lead to toxicity. In all locations, there was decrease in the levels of each metal in the samples with (5 - 10 cm) depth.展开更多
Soil loss through erosion continues to pose serious challenges to increasing the smallholder agricultural productivity in Sierra Leone. While emphasis on sustainable land use practices continue to gain attention among...Soil loss through erosion continues to pose serious challenges to increasing the smallholder agricultural productivity in Sierra Leone. While emphasis on sustainable land use practices continue to gain attention among land users, however, the rate of adoption among smallholder farmers is still very low and hence, in most part of the country soil fertility has been declining at alarming rates. In the Njala area, studies have shown that soil loss ranges from moderate to high. Though soil erosion has been identified as a major soil fertility declining factor, however, the effect of land use practices on the inherent resistance of soil materials to erosion is lacking. This study was therefore conducted to assess the effect of land uses on soil erodibility. The results showed that the soils are coarse sandy loam with high sand content. The dispersion ratios and erosion indices of soils under cassava, plantain, maize and guava were above the minimum thresholds of 15.0 and 10.0 respectively, thus indicating that these soils are highly erodible compared to soils under fallow and sweet potato which have dispersion ratios and erosion indices below the minimum thresholds. Clay content was inversely proportional to and significantly correlated with dispersion ratio and erosion index while the correlations between silt + clay, dispersion ration and erosion index, and silt, silt + clay and dispersion ratio were negative and non-significant. Considering the coarse nature of soils, landscape features and high erodibility indices, these soils would need special soil and water conservation practices to counter further degradation. These may include following, agroforestry, silvi-pasture, controlled and rotational grazing. In addition, awareness of sense of self-responsibility and forest policies and regulations are needed.展开更多
Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Si...Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Sierra Leone. The population of the area has vastly out-grown the infrastructure laid down before and since independence. De-centralization of authority to local councils as recommended post-war has only been partial. The role of local versus central government in the planning and maintenance of water, sanitation and market-infrastructure and related policies was explored. This is a qualitative study that used semi-structured interviews with vendors, consumers and 29 key informants. Amongst an estimated population of 5386 actors in food services a sample size of 309 vendors, consumers in and around the 12 busiest market hubs in Western Area Urban and Rural Districts were sampled. Most of the respondents described “food safety” as “good-to-eat, well taken care-off, and free from germs”. The respondents cited that main causes to unsafe food are poor hygienic practices: 38%, contamination by flies: 28%, uncovered food/ improper handling/poor personal hygiene: 21%, and environmental factors, such as improper refuse disposal: 11%. Respondents expressed that consuming unsafe foods can lead to diarrhoea: 34%, food poisoning: 24%, vomiting: 17%, stomach ache/pain: 16%, or typhoid: 9%. Various measures to improve food safety were cited as hand washing: 60%, cleaning surroundings: 57%, covering food: 56%, washing utensils: 52%, covering hair: 42% and using a face mask: 32%. However almost 76% of food vendors interviewed were trading near gutters, where muddy/dirty water settled, with slippery floors, discarded plastic waste, flies and inadequate water, sanitation, and/or storage facilities. None of the food vendors had had any formal training on food safety. Despite progress recently made in solid and liquid waste management during the “Transform Freetown” agenda much more improvement in infrastructure and behaviour change is required. Similarly, despite improvements in formal market facilities the pattern of informal street trading remains the most prevalent especially for the poor. The link between “safe food” and good health was only partially understood, whilst the widespread application of recommended practices to reduce risks was lacking due in part to inadequate infrastructure. As the importance of food safety becomes better understood by administrators and the public the investments required in infrastructure and social and behavioural change will contribute towards a healthier environment and outcomes.展开更多
The use of artificial diets to mass reared insect stock under laboratory conditions, promotes knowledge about the biology, behavior, and nutritional requirements of insects;with such information being fundamental for ...The use of artificial diets to mass reared insect stock under laboratory conditions, promotes knowledge about the biology, behavior, and nutritional requirements of insects;with such information being fundamental for the formulation of efficient integrated pest management programs (IPM) strategies. However, the artificial diets used for rearing Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in the laboratory in this study, do not contain wheat germ, used for routine laboratory rearing. The aim of this study was to compare food preference and consumption by S. frugiperda larvae, as well as evaluate insect developmental parameters in the standard diet and the bean-based diets under laboratory conditions. Four artificial diets were used: a standard diet based on broad beans (Phaseolus vulgaris L.) used to rear S. frugiperda (D1), a diet with the substitution of two types of beans, cowpea (Vigna unguiculata L.) (D2) and pigeon pea (Cajanus cajan L) (D3);and a diet of fresh corn leaves (D4), the host plant of the pest species. Using a multiple-choice test, we observed that the larvae preferred diets D4 followed by D1. The relative consumption rate (RCR), relative growth rate (RGR), relative metabolic rate (RMR), approximate digestibility (AD), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and the metabolic cost (CM) for S. frugiperda fifth instar larvae varied among diets. The diet D4 resulted in better ingestion, digestion, assimilation, and conversion of food, but with a metabolic cost to assimilate the food. The different bean varieties present in the diet influenced larval length, larval periods, larval survival, pupal periods, sex ratio, pupal weight, and pupal survival;but fecundity and longevity of adults were not affected. The different bean-based diets did positively influence population growth, with the most outstanding being D4. From the results of this study, the most adequate diet for rearing S. frugiperda in the laboratory is D4.展开更多
The thrust of this research study was to ascertain the physicochemical characteristic in settling particulate matter and sediments of samples collected from the wellington industrial estate flood plains;the main of ob...The thrust of this research study was to ascertain the physicochemical characteristic in settling particulate matter and sediments of samples collected from the wellington industrial estate flood plains;the main of objectives are as follows: to determine the hydrogen ion index (pH) of the samples collected in the study area, to determine the electrical conductivity (EC) of the samples collected from the same location. Samples were collected from six locations (at varying depths of 0 - 5 cm and 5 - 10 cm) sample area 1 (Wellington Industrial Estate Area 1) WIEA1 WIEA 2, WIEA 3, WIEA 4, WIEA 5 and WIEA 6 and were given laboratory treatment. A laboratory thermometer was used to determine temperature of the samples when collected;(Dakton model) pH meter equipment and a Toledo electrical conductivity meter were used to determine the pH and EC respectively. The results indicated that the samples were acidic (low pH) and the conductivity of the samples was of medium and low range. This therefore expressed low levels of soluble metal ions in the environment that have effect on plants, animals and other organisms, agricultural and domestic activities in the environment under investigation. Hence bioconcentration and biomagnification are highly likely in these locations.展开更多
A better understanding of population structure and genetic diversity among cassava germplasm for African cassava mosaic disease and fresh root yield traits is useful for cassava improvement programme. Phenotype-based ...A better understanding of population structure and genetic diversity among cassava germplasm for African cassava mosaic disease and fresh root yield traits is useful for cassava improvement programme. Phenotype-based selection for these traits is cumbersome due to phenotypic plasticity and difficulty in screening of phenotypic-induced variations. This study assessed quantitative trait loci (QTL) regions associated with African cassava mosaic disease (ACMD) and fresh storage root yield (FSRY) in 131 cassava (Manihot esculenta) genotypes using a genome-wide association study (GWAS). The single nucleotide polymorphism (SNP) loci and associated candidate genes, when validated, would be a valuable resource for marker-assisted selection in the breeding process for development of new cassava genotypes with improved resistance to ACMD and desirable high root yield. Population structure analysis using 12,500 SNPs differentiated the 131 genotypes into five distinct sub-groups (K = 5). Marker-trait association (MTA) analysis using the generalized linear model identified two QTL regions significant for ACMD and three for FSRY. This study demonstrated that DArTseq markers are useful genomic resources for genome-wide association studies of ACMD and FSRY traits in cassava for the acceleration of varietal development and release.展开更多
It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge...It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge (ITK) of the diversity of cassava varieties in terms of: their morphology, growth characteristics, uses (of tubers and leaves) and desirable characteristics. The objective is to see to what extent the objectives of the plant breeders are consistent with what farmers’ value. We performed 405 structured and semi-structured interviews with informants who were selected based on “purposive household sampling”. We found a considerable turn-over in cassava varieties, just over a third (45) have been in cultivation for at least 40 years, however, since the end of the civil war an additional 25 varieties are cultivated, while others varieties seem to have disappeared. One major issue with estimating turnover of varieties is whether the same variety might have several local names, and conversely the same name may be applied to different cultivars. Farmers overwhelmingly use ITK to select and preserve cassava germplasm for future use. Farmers have a clear preference for: sweet taste, high yield, early maturity and easy cooking and preferentially adopt cultivars that have those qualities. Cassava is primarily a human food eaten boiled or fried, some are processed into fufu and gari, and uses as livestock feed and medicine are reported but at low levels. The information produced during this study could help plant breeders choose selection criteria that will ensure their efforts are adopted and sustainable, the importance of preserving the genetic resources of local cultivars is also highlighted.展开更多
Coffee is a major cash and export crop in Sierra Leone and is mainly cultivated in southern and eastern provinces.Kenema,Kailahun,Moyamba,Bo,Pujehun and Kono are major coffee growing districts in the country.This stud...Coffee is a major cash and export crop in Sierra Leone and is mainly cultivated in southern and eastern provinces.Kenema,Kailahun,Moyamba,Bo,Pujehun and Kono are major coffee growing districts in the country.This study looks at the extent of phenotypic diversity of the rare and wild Coffea stenophylla in Kenema and Moyamba districts.The Shannon-Weaver diversity index(H')revealed variations among the samples for the observed 13 morphological traits which ranges from 0 for both fruit colour and calyx limb persistence to 0.87 for angle of insertion of primary branches on the main stem.Among the 13 morphological traits assessed,angle of insertion of primary branches on main stem(0.87),growth habit(0.78),bean size(0.75),young leaf colour(0.66),stem habit(0.66)and fruit shape(0.65)exhibited high level of diversity while seed shape(0.58),stipule shape(0.46),leaf shape(0.43),seed uniformity(0.31)and leaf apex shape(0.06)showed low levels of diversity.This is the first report of phenotypic diversity of C.stenophylla in Sierra Leone and the study thus unraveled existence of diversity among samples.It is recommended that these observed variabilities be exploited in order to develop better accessions that are high yielding yet maintain the same taste.Additionally,genetic fingerprinting needs to be applied to provide a complementary assessment of the observed phenotypic diversity.展开更多
Global coffee production is dominated by Coffea arabica(Arabica coffee)and C.canephora(Robusta coffee)due to their relatively high-yielding and quality attributes as opposed to other coffee species.Despite these advan...Global coffee production is dominated by Coffea arabica(Arabica coffee)and C.canephora(Robusta coffee)due to their relatively high-yielding and quality attributes as opposed to other coffee species.Despite these advantages,production of Arabica and Robusta coffee is facing mounting challenges though not limited to increasing prevalence and severity of biotic and abiotic stresses.These challenges bring forth an indication that the global coffee crop portfolio requires diversification to ensure resilience to the key challenges for sustainable production.Sierra Leone is in the center of genetic diversity of genus Coffea,and the country hosts rich coffee genetic resources.The C.stenophylla,C.affinis and possibly other wild relative species are indigenous to Sierra Leone and these species offer great potential for a new coffee market and income generation.However,more efforts of conservation and genetic improvement on these species,are needed to realize these opportunities.The objective of this paper is to review the coffee genetic resources in Sierra Leone with an emphasis on the wild coffee species including their conservation status,and the phenotypic and molecular characterization.We also present perspectives for future genetic improvement of C.stenophylla,and discuss breeding methods,combining ability,and molecular marker-assisted prediction of hybrid vigor.Moreover,with the availability of recently developed single nucleotide polymorphisms(SNP)markers on C.stenophylla,we suggest that new technologies of molecular breeding,such as genomic selection can significantly accelerate the breeding progress and deliver improved varieties with high yield,good adaptability,and disease resistance.展开更多
文摘Suppliers of potable water would benefit from a sustainable business as long as consumers continue to prefer their brand. Some of the reasons for choosing a particular brand include water quality, cost of the finished product, reliability of supply, and supplier ethics. These important determinant factors form the basis of this work. The objective is to delineate consumer preferences for water supplied to the Njala campus community, in southern Sierra Leone, and the underlying determinant factors. A list of questions administered to 140 respondents, are used to help achieve the objective. The results of water quality tests are also used to determine if quality has anything to do with consumer preference. The Oxfam Delagua water testing kit is customized to incubate and enhance counting of fecal and no-fecal coliform bacteria in water samples. Bacterial contamination is the major concern in the study area. The survey results reveal the consumers prefer package water for drinking. Treated water from Tia River is only used for other domestic purposes. The consumers do not trust the quality of water supplied from Tia River, albeit filtration and disinfection at the University’s treatment center. This distrust is confirmed by the bacterial test. None of the campus water sources meet recommended guidelines for drinking water. The consumers are, however, willing to shift preference from package to tap drinking water if treatment comes with quality assurance. The university could benefit through economic gratification, customer protection, and reduced plastic waste from package drinking water.
文摘The safety of water is usually determined by comparing its quality to recommended standards. The objective of this work was to determine whether the water supplied on Njala Campus is safe for drinking. The quality parameters investigated include coliform bacteria, turbidity, conductivity, total dissolved solids and nitrates. Samples were stored in a cooler with ice and transported to the laboratory within 30 minutes of collection. A checklist of questions to know the perception of residents was administered. According to the physical and biological results, the water is not safe for consumption. The turbidity and microbial counts were too high in most samples both in the wet and dry seasons. Additionally, over 80% of the respondents did not trust the water supply system. Most of them treat the supplied water by either boiling or disinfection before use. Most respondents complained of water-borne diseases but were not clear whether it is related to the water supplied. The chemical parameters, however, were acceptable: nitrate levels were low. In conclusion, the water is not safe for consumption as far as the physical and biological parameters are concerned. The campus water supply system needs improvement in terms of conveying raw and finished water, filter optimization, and satisfying the chlorine demand.
文摘This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup>) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p < 0.05) influenced grain yield production. Mean grain yields and economic parameter estimates increased with increasing nitrogen rates, with the 30 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup> plots exhibiting the lowest and highest grain yields of 1238 kg∙ha<sup>−</sup><sup>1</sup> and 2098 kg∙ha<sup>−</sup><sup>1</sup>, respectively. Variety and nitrogen effects on partial factor productivity (PFP<sub>N</sub>), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p < 0.05) by these factors. The highest PFP<sub>N</sub> (41.3 kg grain kg<sup>−</sup><sup>1</sup>∙N) and AEN (29.4 kg grain kg<sup>−</sup><sup>1</sup>∙N) were obtained in the 30 kg∙N∙ha<sup>−</sup><sup>1</sup> plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL<sup>−</sup><sup>1</sup> spent on N) were obtained in the 180 kg∙N∙ha<sup>−</sup><sup>1</sup>. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fertilization and improved farming practices that could be exploited for increased productivity of maize.
文摘This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Foya Wulleh, Njala experimental site in Sierra Leone during 2020 and 2021 cropping seasons in a randomized complete block design with three replications. A total of 30 genotypes comprising 26 breeding lines, two improved and two local genotypes were assessed. Results showed a significant (p < 0.05) linear relationship between leaf CNP and grasshopper infestation (incidence and severity of damage) among cassava genotypes. Findings showed that the higher leaf CNP, the lower the grasshopper infestation in cassava genotypes. About two genotypes (Cooksoon and Cocoa) had low leaf CNP;three genotypes (TR0020, TR0037 and TR0013) CNP had moderately low leaf CNP;eight genotypes (SLICASS 6, TR0029, TR0032, TR0011, TR0012, TR0016-1/17, TR0002 and TR0010) had intermediate leaf CNP;seven (TR0009, TR0015-1/17, TR0036, TR0022-1/17, SLICASS 4, TR0007 and TR0026-1/17) had moderately high leaf CNP;eight (TR0008, TR0019-1/17, TR0006, TR0005, TR0021, TR0021-1/17, TR0022 and TR0024-1/17) had high leaf CNP;and two genotypes (TR0001 and TR0018-1/17) had very high leaf CNP. This suggests the indirect dependence of leaf cyanogenic potential on grasshopper infestation (incidence and severity of damage) in cassava that could be exploited for the genetic improvement of cassava for improved resistance to grasshopper infestation, nutrition and utilization of the crop.
文摘The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6). Fresh cassava roots harvested from the Department of Agricultural Engineering were peeled, washed and grated before fermentation and starch extraction. Fermentation was carried out under separate aerobic and anaerobic conditions for a period of Seven days. Physicochemical analyses were conducted at the Postharvest Food and Bioprocess Engineering Laboratory of the Department of Agricultural and Bio-System Engineering, Njala University to determine the solubility, water absorption capacity and swelling power of starch extracts obtained from various experimental treatments. Fermentation method and duration had significant effects on the solubility, water absorption capacity (WAC) and swelling power (SP) of starch extracts. Maximum solubility and WAC were recorded on the fifth day, for both cassava varieties tested, with apparent significant difference resulting from the two gratering bands (i.e., with 1.5-inch nail hole and 4-inch nail hole sizes, respectively). While swelling power increased consistently with temperature for starch obtained from SLICASS-11 variety, an irregular pattern was observed for SLICASS-6 variety. A multiple correlation analysis proposes a significant and weak correlation between temperature, WAC (+0.150) and swelling power (+0.048). Also multiple correlation analyses suggest a significant correlation between fermentation period, the functional properties of starch extracts obtained from both fermentation methods and cassava varieties (i.e., solubility (−0.226), water absorption capacity (+0.301) and swelling power (+0.329)).
文摘Low nutrient density and bulkiness of complementary foods, early introduction of solid foods, and unhygienic practices during weaning stage of a child predispose infants to malnutrition, growth retardation, infection and high mortality. In most West African countries, especially in Sierra Leone, the use of a variety of home-made complementary foods prepared from locally grown foodstuffs during the weaning process is popular, with products traditionally known as pap (mesh rice water) fofo from cassava, ogi, gari, akamu and couscous. Sierra Leone is one of the countries in West Africa that has been reported to have a challenging situation with regards to complementary foods, and little effort has so far been done to improve the situation. Despite these challenges, very little work has been directed towards the development of complementary foods using local foodstuffs as practiced in some other African countries. This situation has serious impact on the lives of infants in Sierra Leone, thus increasing the rate of mortality in the country. Complementary food situation in Sierra Leone was reviewed in terms of the past and present practices as well as the types of complementary foods used in Sierra Leone. Thus, the objective of this review was to discuss the complementary food situation in Sierra Leone: Nutritional problems and possible strategies. Formulation of high nutritive value home-made complementary foods in the country was recommended using traditional food processing techniques such as fermentation and germination, since these methods are simple, and could easily be employed at household and community levels without the use of sophisticated machinery. Nonetheless, it was recently reported that a product from the orange-flesh sweet potato could address the issue of complementary food in the country as it is easy to prepare, and the products are easily available in the rural area and even urban settings. Other recommendations made include: community nutrition education, the development of weaning recipe book, reduction in the workload of the suckling mother, promotion of breastfeeding and increased maternity leave period, which were suggested to be the most immediate possible strategies for the problems highlighted.
文摘Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and service. Unsafe food can cause illness keeping people from achieving their full potential and death. This was a descriptive study that uses a mixed method approach to derive insights into the characteristics of food vendors related to demography, knowledge, practices, infrastructure, compliance and recommendation for a policymaking framework. Using the Lemeshows’ sample size formula, 473 vendors from formal (restaurants) and informal (cookri-baffa/table top) sites were interviewed and observed. We found from discussions that respondents had a good understanding on how to keep food safe. However, observed practices were poor 93% handled food with their bare hands, 83% did not cover their hair, and 76% did not wear an apron whilst handling, preparing or serving food, 61% did not keep their finger nails clean or short and 57% did not wash their hand before preparing or serving food. Over half (51%) had access to a toilet but 32% reported their use required payment and emphasized their poor condition/inadequate management. Nearly half (47%) of the vending sites did not have a handwashing facility, with soap and water available. Only 7% reported having any authority oversight of food safety. Food safety and hygiene practices in most cookri shops and restaurants was ‘poor’ with very limited surveillance system in place by competent authorities for compliance of food operators. Hand washing, clean surroundings, and covered food were the most common and emphasized practices to mitigate the risks associated with unsafe food.
文摘This study evaluated the variation in yellow root cassava (Manihot esculentus Crantz) genotypes and phenotypic relationship for selected postharvest and morphological traits. The trial was established at the Njala Agricultural Research Centre experimental site, Njala, during 2017/2018 cropping season in a randomized complete block design with three replications. Findings showed that the higher the total carotene content (TCC) in yellow flesh cassava genotypes, the longer the rate of postharvest physiological deterioration (PPD). Genotypes TR-0051-TCC/17 and TR-0012-TCC/17 recorded higher TCC (18.9 µg/g and 13.6 µg/g) and longer rate of PPD (4.29 and 3.14), respectively. Genotypes TR-0051-TCC/17, TR-0016-TCC/17, TR-0028-TCC/17, TR-0012-TCC/17 and TR-0020-TCC/17 had the highest TCC values of 18.9 µg/g, 16.09 µg/g, 14.72 µg/g, 13.6 µg/g and 11.23 µg/g with corresponding higher color chart values of 6, 6, 6, 5, and 6, respectively. This suggests the direct dependence of TCC on the root parenchyma color intensity in yellow flesh cassava genotypes. Findings also show a direct relationship between morphological and postharvest traits in yellow flesh cassava genotypes that could be exploited for the genetic improvement of cassava for increased shelf life, nutrition and related quality traits, as well as conservation and utilization of the crop.
文摘Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.
文摘Artificial fishponds play a pivotal role in global aquaculture, serving as a source of livelihood and nourishment for many communities. Ensuring the sustained health and productivity of Fishes in these environments relies heavily on water quality management. This assessment was done to determine the water quality of ten artificial fishponds in the south-eastern part of Sierra Leone using twelve physicochemical factors (pH, BOD, EC, TDS, turbidity, COD, Fe<sup>2+</sup>, Mg<sup>2+</sup>, Ca<sup>2+</sup>, NH<sub>3</sub>, , and alkalinity) to find out the Water Quality Index (WQI) and spatial distribution of respective parameters. The assessment of artificial fishponds using WQI and Inverse Distant Weighting (IDW) integration represents a relatively underexplored area within the domain of environmental water resources. The WQI was determined using the “Weighted Arithmetic Water Quality Index’’ method. The results of WQI in the study area range from 65.05 to 147.26. Several locations have water quality deemed unsuitable for consumption, while others range from good to very poor. It is essential to address and improve water quality in locations categorized as unsuitable for consumption and very poor to ensure safe and healthy water sources. It was also clear from the calculation that the smaller the mean concentration value of the pH as compared to the ideal value (7), the smaller the WQI value and the better the water quality. To keep the artificial fishpond water in good condition, mass domestic use should be controlled, and draining of surrounding organic matter should be stopped in ponds Bo_001, Kenema_001, and Kenema_002.
文摘Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasing across the globe. In this study, the physical parameters of potable well waters in the key mining areas in Nimikoro and Tankoro Chiefdoms in Kono District were analyzed for compliance with drinking water quality standard. To do this, both unpurged and purged well water samples were collected once every month for a period of one year. Some of the well water properties like temperature, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were measured on site and others determined in the laboratory. The data collected from the laboratory analyses were statistically analyzed in MS Excel, SPSS and ArcGIS environments for quality trends in time-space fabric. The results showed that well water quality in the study area generally fell short of drinking water quality standards of Sierra Leone and WHO. There were high temperature and turbidity during the dry season and then high TDS and EC during the rainy season. Temperature and turbidity also significantly influenced well water quality in the study area, much more than TDS and EC. The implications for drinking water of lower quality than the standard could be huge for the local population and therefore needs the attention of stakeholders in the study area and decision makers in the country.
文摘This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) determine calcium and magnesium, 3) determine available iron. The following hypotheses were put forward;H<sub>0</sub><sub>a</sub>: there is no significant difference in the concentration levels between Ca and Mg in the study area, H<sub>1</sub><sub>a</sub>: there is significant difference in the concentration levels between Ca and Mg in the study area, H<sub>0</sub><sub>b</sub>: there is no significant difference in the concentration levels between Na and K in the study area, H<sub>1</sub><sub>b</sub>: there is significant difference in the concentration levels between Na and K in the study area. Six locations were used to collect samples with the aid of scoop and gravel free auger (at varying depths of 0 - 5 cm and 5 - 10 cm) which are Wellington Industrial Estate Area 1 (WIEL 1), (WIEL 2), (WIEL 3), (WIEL 4), (WIEL 5), (WIEL 6);the samples were given laboratory treatment. Flame photometer, EDTA, and Spectrophotometer were used in the determinations of sodium and potassium, calcium and magnesium, and available iron respectively. The results indicated that levels of potassium were in medium range (moderately high);sodium levels were generally low when compared to Brook’s classification table. Levels of calcium were generally low and those of magnesium were moderate based on Brook’s table of classification. Levels of available iron which fall within the range of Quijano-Guerta (2003) were high;this implies such levels can lead to toxicity. In all locations, there was decrease in the levels of each metal in the samples with (5 - 10 cm) depth.
文摘Soil loss through erosion continues to pose serious challenges to increasing the smallholder agricultural productivity in Sierra Leone. While emphasis on sustainable land use practices continue to gain attention among land users, however, the rate of adoption among smallholder farmers is still very low and hence, in most part of the country soil fertility has been declining at alarming rates. In the Njala area, studies have shown that soil loss ranges from moderate to high. Though soil erosion has been identified as a major soil fertility declining factor, however, the effect of land use practices on the inherent resistance of soil materials to erosion is lacking. This study was therefore conducted to assess the effect of land uses on soil erodibility. The results showed that the soils are coarse sandy loam with high sand content. The dispersion ratios and erosion indices of soils under cassava, plantain, maize and guava were above the minimum thresholds of 15.0 and 10.0 respectively, thus indicating that these soils are highly erodible compared to soils under fallow and sweet potato which have dispersion ratios and erosion indices below the minimum thresholds. Clay content was inversely proportional to and significantly correlated with dispersion ratio and erosion index while the correlations between silt + clay, dispersion ration and erosion index, and silt, silt + clay and dispersion ratio were negative and non-significant. Considering the coarse nature of soils, landscape features and high erodibility indices, these soils would need special soil and water conservation practices to counter further degradation. These may include following, agroforestry, silvi-pasture, controlled and rotational grazing. In addition, awareness of sense of self-responsibility and forest policies and regulations are needed.
文摘Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Sierra Leone. The population of the area has vastly out-grown the infrastructure laid down before and since independence. De-centralization of authority to local councils as recommended post-war has only been partial. The role of local versus central government in the planning and maintenance of water, sanitation and market-infrastructure and related policies was explored. This is a qualitative study that used semi-structured interviews with vendors, consumers and 29 key informants. Amongst an estimated population of 5386 actors in food services a sample size of 309 vendors, consumers in and around the 12 busiest market hubs in Western Area Urban and Rural Districts were sampled. Most of the respondents described “food safety” as “good-to-eat, well taken care-off, and free from germs”. The respondents cited that main causes to unsafe food are poor hygienic practices: 38%, contamination by flies: 28%, uncovered food/ improper handling/poor personal hygiene: 21%, and environmental factors, such as improper refuse disposal: 11%. Respondents expressed that consuming unsafe foods can lead to diarrhoea: 34%, food poisoning: 24%, vomiting: 17%, stomach ache/pain: 16%, or typhoid: 9%. Various measures to improve food safety were cited as hand washing: 60%, cleaning surroundings: 57%, covering food: 56%, washing utensils: 52%, covering hair: 42% and using a face mask: 32%. However almost 76% of food vendors interviewed were trading near gutters, where muddy/dirty water settled, with slippery floors, discarded plastic waste, flies and inadequate water, sanitation, and/or storage facilities. None of the food vendors had had any formal training on food safety. Despite progress recently made in solid and liquid waste management during the “Transform Freetown” agenda much more improvement in infrastructure and behaviour change is required. Similarly, despite improvements in formal market facilities the pattern of informal street trading remains the most prevalent especially for the poor. The link between “safe food” and good health was only partially understood, whilst the widespread application of recommended practices to reduce risks was lacking due in part to inadequate infrastructure. As the importance of food safety becomes better understood by administrators and the public the investments required in infrastructure and social and behavioural change will contribute towards a healthier environment and outcomes.
文摘The use of artificial diets to mass reared insect stock under laboratory conditions, promotes knowledge about the biology, behavior, and nutritional requirements of insects;with such information being fundamental for the formulation of efficient integrated pest management programs (IPM) strategies. However, the artificial diets used for rearing Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in the laboratory in this study, do not contain wheat germ, used for routine laboratory rearing. The aim of this study was to compare food preference and consumption by S. frugiperda larvae, as well as evaluate insect developmental parameters in the standard diet and the bean-based diets under laboratory conditions. Four artificial diets were used: a standard diet based on broad beans (Phaseolus vulgaris L.) used to rear S. frugiperda (D1), a diet with the substitution of two types of beans, cowpea (Vigna unguiculata L.) (D2) and pigeon pea (Cajanus cajan L) (D3);and a diet of fresh corn leaves (D4), the host plant of the pest species. Using a multiple-choice test, we observed that the larvae preferred diets D4 followed by D1. The relative consumption rate (RCR), relative growth rate (RGR), relative metabolic rate (RMR), approximate digestibility (AD), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and the metabolic cost (CM) for S. frugiperda fifth instar larvae varied among diets. The diet D4 resulted in better ingestion, digestion, assimilation, and conversion of food, but with a metabolic cost to assimilate the food. The different bean varieties present in the diet influenced larval length, larval periods, larval survival, pupal periods, sex ratio, pupal weight, and pupal survival;but fecundity and longevity of adults were not affected. The different bean-based diets did positively influence population growth, with the most outstanding being D4. From the results of this study, the most adequate diet for rearing S. frugiperda in the laboratory is D4.
文摘The thrust of this research study was to ascertain the physicochemical characteristic in settling particulate matter and sediments of samples collected from the wellington industrial estate flood plains;the main of objectives are as follows: to determine the hydrogen ion index (pH) of the samples collected in the study area, to determine the electrical conductivity (EC) of the samples collected from the same location. Samples were collected from six locations (at varying depths of 0 - 5 cm and 5 - 10 cm) sample area 1 (Wellington Industrial Estate Area 1) WIEA1 WIEA 2, WIEA 3, WIEA 4, WIEA 5 and WIEA 6 and were given laboratory treatment. A laboratory thermometer was used to determine temperature of the samples when collected;(Dakton model) pH meter equipment and a Toledo electrical conductivity meter were used to determine the pH and EC respectively. The results indicated that the samples were acidic (low pH) and the conductivity of the samples was of medium and low range. This therefore expressed low levels of soluble metal ions in the environment that have effect on plants, animals and other organisms, agricultural and domestic activities in the environment under investigation. Hence bioconcentration and biomagnification are highly likely in these locations.
文摘A better understanding of population structure and genetic diversity among cassava germplasm for African cassava mosaic disease and fresh root yield traits is useful for cassava improvement programme. Phenotype-based selection for these traits is cumbersome due to phenotypic plasticity and difficulty in screening of phenotypic-induced variations. This study assessed quantitative trait loci (QTL) regions associated with African cassava mosaic disease (ACMD) and fresh storage root yield (FSRY) in 131 cassava (Manihot esculenta) genotypes using a genome-wide association study (GWAS). The single nucleotide polymorphism (SNP) loci and associated candidate genes, when validated, would be a valuable resource for marker-assisted selection in the breeding process for development of new cassava genotypes with improved resistance to ACMD and desirable high root yield. Population structure analysis using 12,500 SNPs differentiated the 131 genotypes into five distinct sub-groups (K = 5). Marker-trait association (MTA) analysis using the generalized linear model identified two QTL regions significant for ACMD and three for FSRY. This study demonstrated that DArTseq markers are useful genomic resources for genome-wide association studies of ACMD and FSRY traits in cassava for the acceleration of varietal development and release.
文摘It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge (ITK) of the diversity of cassava varieties in terms of: their morphology, growth characteristics, uses (of tubers and leaves) and desirable characteristics. The objective is to see to what extent the objectives of the plant breeders are consistent with what farmers’ value. We performed 405 structured and semi-structured interviews with informants who were selected based on “purposive household sampling”. We found a considerable turn-over in cassava varieties, just over a third (45) have been in cultivation for at least 40 years, however, since the end of the civil war an additional 25 varieties are cultivated, while others varieties seem to have disappeared. One major issue with estimating turnover of varieties is whether the same variety might have several local names, and conversely the same name may be applied to different cultivars. Farmers overwhelmingly use ITK to select and preserve cassava germplasm for future use. Farmers have a clear preference for: sweet taste, high yield, early maturity and easy cooking and preferentially adopt cultivars that have those qualities. Cassava is primarily a human food eaten boiled or fried, some are processed into fufu and gari, and uses as livestock feed and medicine are reported but at low levels. The information produced during this study could help plant breeders choose selection criteria that will ensure their efforts are adopted and sustainable, the importance of preserving the genetic resources of local cultivars is also highlighted.
文摘Coffee is a major cash and export crop in Sierra Leone and is mainly cultivated in southern and eastern provinces.Kenema,Kailahun,Moyamba,Bo,Pujehun and Kono are major coffee growing districts in the country.This study looks at the extent of phenotypic diversity of the rare and wild Coffea stenophylla in Kenema and Moyamba districts.The Shannon-Weaver diversity index(H')revealed variations among the samples for the observed 13 morphological traits which ranges from 0 for both fruit colour and calyx limb persistence to 0.87 for angle of insertion of primary branches on the main stem.Among the 13 morphological traits assessed,angle of insertion of primary branches on main stem(0.87),growth habit(0.78),bean size(0.75),young leaf colour(0.66),stem habit(0.66)and fruit shape(0.65)exhibited high level of diversity while seed shape(0.58),stipule shape(0.46),leaf shape(0.43),seed uniformity(0.31)and leaf apex shape(0.06)showed low levels of diversity.This is the first report of phenotypic diversity of C.stenophylla in Sierra Leone and the study thus unraveled existence of diversity among samples.It is recommended that these observed variabilities be exploited in order to develop better accessions that are high yielding yet maintain the same taste.Additionally,genetic fingerprinting needs to be applied to provide a complementary assessment of the observed phenotypic diversity.
文摘Global coffee production is dominated by Coffea arabica(Arabica coffee)and C.canephora(Robusta coffee)due to their relatively high-yielding and quality attributes as opposed to other coffee species.Despite these advantages,production of Arabica and Robusta coffee is facing mounting challenges though not limited to increasing prevalence and severity of biotic and abiotic stresses.These challenges bring forth an indication that the global coffee crop portfolio requires diversification to ensure resilience to the key challenges for sustainable production.Sierra Leone is in the center of genetic diversity of genus Coffea,and the country hosts rich coffee genetic resources.The C.stenophylla,C.affinis and possibly other wild relative species are indigenous to Sierra Leone and these species offer great potential for a new coffee market and income generation.However,more efforts of conservation and genetic improvement on these species,are needed to realize these opportunities.The objective of this paper is to review the coffee genetic resources in Sierra Leone with an emphasis on the wild coffee species including their conservation status,and the phenotypic and molecular characterization.We also present perspectives for future genetic improvement of C.stenophylla,and discuss breeding methods,combining ability,and molecular marker-assisted prediction of hybrid vigor.Moreover,with the availability of recently developed single nucleotide polymorphisms(SNP)markers on C.stenophylla,we suggest that new technologies of molecular breeding,such as genomic selection can significantly accelerate the breeding progress and deliver improved varieties with high yield,good adaptability,and disease resistance.